The Role of Neuronal Ensembles Supporting Auditory Fear Conditioning (Engrams) in the Amygdala in Memory Formation, Generalization and Extinction

项目摘要/摘要 记忆可以被定义为通过以下方式获得的内部表征随时间的保持 经验，以及在以后重建这些陈述的能力(Dudai 2007)。 这些内部表征被认为是由持久的物理大脑编码的 变化(记忆痕迹或字母)(Josselyn，Kohler&Frankland 2015,2017；Tonegawa et 艾尔2015年；Schacter 2001年)。记住引起恐惧的事件是适应性的；它帮助一个人 基于过去经验的未来选择。将一些令人恐惧的事情概括起来甚至可能是有益的 回忆。然而，过度的恐惧泛化或将不再具有威胁性的刺激视为 危险可能是不适应的。事实上，反复出现或不适当地表达恐惧 记忆是几种精神疾病的主要组成部分，包括创伤后疾病 应激障碍(PTSD)和焦虑。因此，了解记忆是如何追踪恐惧的 事件是形成的，随着时间的推移而变化，在什么条件下它们保持特定或概括， 以及它们如何受到行为灭绝的影响不仅是至关重要的问题 了解大脑如何使用信息，也是为了通知新的 以不适当的恐惧记忆为特征的障碍的治疗/预防策略。 在这里，两个PI(Josselyn博士和Frankland博士)，都是新的调查者，将结合他们的 解决这些重要问题的专业知识。因为所有技术都与 注意事项和限制，我们将使用各种技术，包括光基因操作， 全脑神经元活动图和利用图论生成“印记图” 并将体内实时钙成像与行为相结合。合在一起，有能力 操纵和观察印记的形成、随时间的变化和行为 灭绝是创新的，可能会导致字母的定义发生变化，以及 增加我们对开发旨在解决不适当恐惧的治疗方法的理解 回忆。

Project Summary/Abstract Memory may be defined as the retention over time of internal representations gained through experience, and the capacity to reconstruct these representations at later times (Dudai 2007). These internal representations are thought to be encoded by long-lasting physical brain changes (memory traces or `engrams') (Josselyn, Kohler & Frankland 2015, 2017; Tonegawa et al. 2015; Schacter 2001). Remembering fear-evoking events is adaptive; it helps one make future choices based on past experience. It may even be beneficial to generalize some fearful memories. However, excessive fear generalization or treating no-longer threatening stimuli as dangerous may be maladaptive. Indeed, recurrent or inappropriately expressed fearful memories are a major component of several psychiatric diseases, including post-traumatic stress disorder (PTSD) and anxiety. Therefore, understanding how memory traces for fearful events are formed, change over time, under what conditions they remain specific or generalize, and how they are impacted by behavioral extinction are critical questions to not only understanding how the brain uses information but also for informing the development of new treatment/prevention strategies for disorders characterized by inappropriate fear memories. Here two PIs (Drs. Josselyn and Frankland), both New Investigators, will combine their expertise to address these important questions. Because all techniques are associated with caveats and limitations, we will use a variety of techniques including optogenetic manipulation, brain-wide neuronal activity mapping and the use of graph-theory to produce “engram maps” and real time in vivo calcium imaging combined with behavior. Together, the ability to manipulate and observe an engram as it forms, changes over time and with behavioral extinction is innovative and may lead to a shift in the very definition of an engram, as well as increase our understanding for developing treatments aimed at resolving inappropriate fear memories.